| Label | Statistic Name | Definition | English | Metric |
| ABARRENLCD06 | Area_Barren_from_NLCD2006 | Area of barren from NLCD 2006 class 31 | square miles | km2 |
| ABEL8K | Drainage_Area_below_8000ft | Drainage Area below 8000ft | square miles | km2 |
| ACARBON | Area_of_Carbonate_Rock | Area underlain by carbonate rock | square miles | km2 |
| ACHSWAMP | Area_of_Main_Channel_Swamp | Main Channel Swamp | square miles | km2 |
| ACLAY | Area_of_Lacustrine_Clay_and_Silt | Area underlain by lacustrine clay and silt | square miles | km2 |
| ACROPSNLCD06 | Area_Cultivated_Crops_from_NLCD2006 | Area of area of cultivated crops from NLCD 2006 class 82 | square miles | km2 |
| ACRSDFT | Area_of_Coarse_Stratified_Drift | Area underlain by stratified drift | square miles | km2 |
| ACRSTILL | Area_of_Coarse_Till | Area underlain by coarse-textured glacial till | square miles | km2 |
| ACTIVE | Active_station | Station is currently active | Yes or No | Yes or No |
| ADECIDNLCD06 | Area_Deciduous_from_NLCD2006 | Area of deciduous forest from NLCD 2006 class 41 | square miles | km2 |
| ADETEN | Area_of_Lake_and_Detention_Basin | Lake and Detention Basin Area | square miles | km2 |
| ADEVHINLCD06 | Area_High_developed_NLCD_2006 | Area of developed land, high intensity, NLCD 2006 class 24 | square miles | km2 |
| ADEVLOWNLCD06 | Area_Low_Developed_from_NLCD2006 | Area of developed land, low intensity, from NLCD 2006 class 22 | square miles | km2 |
| ADEVMEDNLCD06 | Area_Medium_developed_NLCD_2006 | Area of developed land, medium intensity, NLCD 2006 class 23 | square miles | km2 |
| ADEVNLCD01 | Developed_area_from_NLCD2001 | Total area of land-use classifications 21-24 from NLCD 2001 | square miles | km2 |
| ADEVNLCD06 | Area_developed_from_NLCD2006 | Area of developed land-use from NLCD 2006 classes 21-24 | square miles | km2 |
| ADEVOPENNLCD06 | Area_Open_Developed_from_NLCD2006 | Area of developed open land from NLCD 2006 class 21 | square miles | km2 |
| ADJCOEFF | Adjustment_Coefficient_From_Page_11 | Coefficient to adjust estimates for percentage of carbonate rock in Western Maryland | dimensionless | dimensionless |
| ADWARFNLCD06 | Area_Dwarf_Scrub_from_NLCD2006 | Area of dwarf scrub from NLCD 2006 class 51 | square miles | km2 |
| AEMERGWETNLCD06 | Area_Emergent_Wetlands_from_NLCD2006 | Area of area of emergent herbaceous wetlands from NLCD 2006 class 95 | square miles | km2 |
| AEVERGRNLCD06 | Evergreen_Forest_NLCD_2006 | Area of evergreen forest from NLCD 2006 class 42 | square miles | km2 |
| AFINMOR | Area_of_End_Moraine_Fine_Till | Area underlain by end moraines of fine-textured till | square miles | km2 |
| AFOREST | Area_of_Forest_Cover | Area covered by forest | square miles | km2 |
| AFORESTNLCD06 | Area_Forest_from_NLCD2006 | Area of forest from NLCD 2006 classes 41-43 | square miles | km2 |
| AG_OF_DA | Ag_Land_Percentage | Agricultural Land in Percentage of Drainage Area (Idaho Logistic Regression Equations SIR 2006-5035 | percent | percent |
| AGLACIER | Area_of_Glaciers | Area covered by glaciers | square miles | km2 |
| AGMD97 | Percent_Agricultural_MDOP97 | Percent area of agricultural land use from Maryland Dept of Planning 1997 land-use data | percent | percent |
| AGRASSNLCD06 | Area_Grassland_from_NLCD2006 | Area of grassland from NLCD 2006 class 71 | square miles | km2 |
| AHERBNLCD06 | Area_Herbaceous_from_NLCD2006 | Area of herbaceous from NLCD 2006 classes 71-74 | square miles | km2 |
| AIMPERV | Area_of_Impervious_Surfaces | Impervious area | square miles | km2 |
| AIMPNLCD01 | Impervious_Area_from_NLCD2001 | Impervious area determined from NLCD 2001 impervious dataset | square miles | km2 |
| AIMPNLCD06 | Area_Impervious_NLCD2006 | Area of impervious land surface determined from NLCD 2006 impervious dataset | square miles | km2 |
| AIMPNLCD10 | Impervious_Area_from_NLCD2001 | Impervious area determined from NLCD 2001 impervious dataset | square miles | km2 |
| ALAKE | Area_of_Lakes_and_Ponds | Area of Lakes and Ponds | square miles | km2 |
| ALICHENNLCD06 | Area_Lichens_from_NLCD2006 | Area of lichens from NLCD 2006 class 73 | square miles | km2 |
| ALIME | Area_of_Limestone | Area underlain by limestone geology | square miles | km2 |
| ALTIND | Altitude_Index | Altitude Index | thousand feet | kilometer |
| AMEDTILL | Medium_Till_Area | Area underlain by medium-textured glacial till | square miles | km2 |
| AMIXFORNLCD06 | Area_Mixed_Forest_from_NLCD2006 | Area of mixed deciduous and evergreen forest from NLCD 2006 class 43 | square miles | km2 |
| AMOSSNLCD06 | Area_Moss_from_NLCD2006 | Area of moss from NLCD 2006 class 74 | square miles | km2 |
| AMUCK | Area_of_Peat_and_Muck | Area underlain by peat and muck | square miles | km2 |
| AOPENLOWNLCD06 | Area_Open_and_Low_NLCD_2006 | Area of developed land, open space and low intensity combined, NLCD2006 classes 21 and 22 | square miles | km2 |
| AOS | Average_Maximum_Overland_Slope | Average Maximum Overland Slope | percent | percent |
| AOUTWASH | Area_of_Outwash | Area underlain by outwash | square miles | km2 |
| APASTURENLCD06 | Area_Pasture_from_NLCD2006 | Area of area of pasture area from NLCD 2006 class 81 | square miles | km2 |
| APLANTNLCD06 | Area_Planted_from_NLCD2006 | Area of planted area from NLCD 2006 classes 81 and 82 | square miles | km2 |
| APRAV | Mean_April_Temperature | Mean April Temperature | degrees F | degrees C |
| APRAVPRE | Mean_April_Precipitation | Mean April Precipitation | inches | mm |
| ARBEL8K | Area_below_8000_ft | Drainage Area below 8000ft | square miles | km2 |
| ASCRUBNLCD06 | Area_Scrub_from_NLCD2006 | Area of scrub from NLCD 2006 classes 51 and 52 | square miles | km2 |
| ASEDGENLCD06 | Area_Sedge_from_NLCD2006 | Area of sedge from NLCD 2006 class 72 | square miles | km2 |
| ASHRUBNLCD06 | Area_Shrub_from_NLCD2006 | Area of shrub scrub from NLCD 2006 class 52 | square miles | km2 |
| ASNOWICENLCD06 | Area_Snow_&_Ice_NLCD2006 | Area of snow and ice from NLCD 2006 class 12 | square miles | km2 |
| ASOILA | Area_of_Hydrologic_Soil_Type_A | Area underlain by hydrologic soil type A | square miles | km2 |
| ASOILASSURGO | SSURGO_Area_of_Hydrologic_Soil_Type_A | Area underlain by hydrologic soil type A from SSURGO | square miles | km2 |
| ASOILASTATSGO | STATSGO_Area_of_Hydrologic_Soil_Type_A | Area underlain by hydrologic soil type A from STATSGO | square miles | km2 |
| ASOILBSSURGO | SSURGO_Area_of_Hydrologic_Soil_Type_B | Area underlain by hydrologic soil type B from SSURGO | square miles | km2 |
| ASOILBSTATSGO | STATSGO_Area_of_Hydrologic_Soil_Type_B | Area underlain by hydrologic soil type B from STATSGO | square miles | km2 |
| ASOILCSSURGO | SSURGO_Area_of_Hydrologic_Soil_Type_C | Area underlain by hydrologic soil type C from SSURGO | square miles | km2 |
| ASOILCSTATSGO | STATSGO_Area_of_Hydrologic_Soil_Type_C | Area underlain by hydrologic soil type C from STATSGO | square miles | km2 |
| ASOILD | Area_of_Hydrologic_Soil_Type_D | Area underlain by hydrologic soil type D | square miles | km2 |
| ASOILDSSURGO | SSURGO_Area_of_Hydrologic_Soil_Type_D | Area underlain by hydrologic soil type D from SSURGO | square miles | km2 |
| ASOILDSTATSGO | STATSGO_Area_of_Hydrologic_Soil_Type_D | Area underlain by hydrologic soil type D from STATSGO | square miles | km2 |
| ASTORAGE | Area_of_Storage | Area of Storage (lakes - ponds - and wetlands ) | square miles | km2 |
| ASTORNLCD06 | Area_Storage_from_NLCD2006 | Area of water bodies and wetlands determined from the NLCD 2006 classes 11, 90 and 95 | square miles | km2 |
| ATILROCK | Area_of_Thin_Till_over_Bedrock | Area underlain by thin glacial till over bedrock | square miles | km2 |
| AUGAV | Mean_August_Temperature | Mean August Temperature | degrees F | degrees C |
| AUGAVPRE | Mean_August_Precipitation | Mean August Precipitation | inches | mm |
| AURBAN | Area_of_Urban_Cover | Area covered by urban land use | square miles | km2 |
| AVMXSS | Average_Maximum_Soil_Slope | Average Maximum Soil Slope | percent | percent |
| AWATERNLCD06 | Area_Water_from_NLCD2006 | Area of water from NLCD 2006 class 11 | square miles | km2 |
| AWATWETNLCD06 | Area_Water_&_Herb_Wetland_NLCD2006 | Area open water and herbaceous wetland from NLCD 2006 classes 11 and 95 | square miles | km2 |
| AWETLAND | Area_of_Wetlands | Area of Wetlands | square miles | km2 |
| AWETLNDLU06 | Area_Wetlands_from_NLCD2006 | Area of wetlands from NLCD 2006 classes 90 and 95 | square miles | km2 |
| AWOODWETNLCD06 | Area_Woody_Wetlands_from_NLCD2006 | Area of area of wooded wetlands from NLCD 2006 class 90 | square miles | km2 |
| AZ_HIPERMA | AZ_Percent_HighPerm_Aquifer | Percent basin surface area containing high permeability aquifer units as defined in SIR 20xx-xxxx | percent | percent |
| AZ_HIPERMG | AZ_Percent_HighPerm_Geologic | Percent basin surface area containing high permeability geologic units as defined in SIR 20xx-xxxx | percent | percent |
| AZIMUTH | Azimuth | Decimal degrees from north of a straight line connecting the points 10- and 85-percent of distance along main stream channel | decimal degrees | decimal degrees |
| BARRENLCD06 | Percent_Barren_from_NLCD2006 | Percentage of barren from NLCD 2006 class 31 | percent | percent |
| BARRENLU92 | Percent_Barren_from_NLCD1992 | Percent Barren from NLCD1992 | percent | percent |
| BARRENNLCD01 | Barren_Land_NLCD_2001 | Percentage of area barren land, NLCD 2001 category 31 | percent | percent |
| BASIN | Drainage_Basin_Code | Local code of major drainage basin in which the station is located | dimensionless | dimensionless |
| BASINPERIM | Basin_Perimeter | Perimeter of the drainage basin | miles | km |
| BASLENAH | Basin_Length_ArcHydro_Method | Basin length from outlet to basin divide determined using the method in the ArcHydro Toolset | miles | km |
| BASSTRMORD | Basin_Stream_Order | Strahler stream order of the main channel at the basin outlet | dimensionless | dimensionless |
| BDF | Basin_Development_Factor | Urbanization index described by Sauer and others (1981) - Also called Urbanization Index in Texas | dimensionless | dimensionless |
| BEGIN_REC | Begin_date_of_record | First day of record | days | days |
| BFI | Base_Flow_Index | Proportion of mean annual flow that is from ground water (base flow) from Wahl and Wahl, 1988 | dimensionless | dimensionless |
| BSLDEM10ff | Mean_Basin_Slope_from_10m_DEM_ft_per_ft | Mean basin slope computed from 10 m DEM in feet per foot | feet per foot | m per m |
| BSLDEM10M | Mean_Basin_Slope_from_10m_DEM | Mean basin slope computed from 10 m DEM | percent | percent |
| BSLDEM250 | Mean_Basin_Slope_from_250K_DEM | Mean basin slope computed from 1:250K DEM | percent | percent |
| BSLDEM30M | Mean_Basin_Slope_from_30m_DEM | Mean basin slope computed from 30 m DEM | percent | percent |
| BSLOPCM | Mean_Basin_Slope_ft_per_mi | Mean basin slope determined by summing lengths of all contours in basin mulitplying by contour interval and dividing product by drainage area | feet per mi | m per km |
| BSLOPD | Mean_Basin_Slope_degrees | Mean basin slope measured in degrees | degrees | degrees |
| BSLOPGM | Mean_Basin_Slope_ft_per_ft | Mean basin slope determined using the grid-sampling method | feet per foot | m per m |
| CANOPY_PCT | Percent_Area_Under_Canopy | Percentage of drainage area covered by canopy as described in OK SIR 2009_5267 | percent | percent |
| CARBADJUST | Carbonate_Adjustment | Binary variable for Western Maryland low-flow equations equals 1 if CARBON greater than 40 percent and zero otherwise | dimensionless | dimensionless |
| CARBON | Percent_Carbonate | Percentage of area of carbonate rock | percent | percent |
| CCM | Constant_of_Channel_Maintenance | Constant of channel maintenance computed as drainage area divided by total stream length | square mile per mile | km2 per km |
| CELVBLUE | Average_Channel_Elevation | Average of outlet elevation and the elevation at the upstream extent of the mapped stream | feet | m |
| CELVMEAN | Mean_Main_Channel_Elevation | Mean elevation along the main channel | feet | m |
| CENTROIDX | Basin_Centroid_X | Basin centroid horizontal (x) location in state plane coordinates | State plane coordinates | State plane coordinates |
| CENTROIDY | Basin_Centroid_Y | Basin centroid vertical (y) location in state plane units | State plane coordinates | State plane coordinates |
| CF | Climate_Factor | Climate factor for area | dimensionless | dimensionless |
| CHANCOND | Average_Channel_Condition | Condition between points 100- 75- 50- and 25-percent along main channel - 2 if entirely paved - 1 if unpaved | dimensionless | dimensionless |
| CHSWAMP | Percent_Main_Channel_Swamp | Percentage of area of main channel swamps | percent | percent |
| CIRC_RATIO | Circularity_Ratio | Circularity Ratio | dimensionless | dimensionless |
| CLENBLUE | Main_Channel_Blue_Line_Length | Length of main channel shown as blue line on a topographic map | miles | km |
| CLIMFACT2YR | 2_Yr_climate_factor_LK1990 | 2-year climate factor from Lichy and Karlinger (1990) | dimensionless | dimensionless |
| CLSL1085LFP | Stream_Slope_10_and_85_Lower_Half | Change in elevation between points 10 and 85 percent of length along the lower half of the longest flow path divided by length between the points | feet per mi | m per km |
| COASTDIST | Distance_From_Coast_To_Basin_Centroid | Shortest distance from Gulf of Maine line along coast to basin centroid | miles | km |
| COMMD97 | Percent_Commercial_MDOP97 | Percent area of commercial land use from Maryland Dept of Planning 1997 land-use data | percent | percent |
| COMPRAT | Compactness_Ratio | A measure of basin shape related to basin perimeter and drainage area | dimensionless | dimensionless |
| CONIF | Percent_Coniferous_Forest | Percentaqe of land surface covered by coniferous forest | percent | percent |
| CONTDA | Contributing_Drainage_Area | Area that contributes flow to a point on a stream | square miles | km2 |
| CONTROL | Percent_Controlled | Percent of basin controlled by lakes swamps and reservoirs | percent | percent |
| CONTROLLED | Percentage_of_Controlled_Area | Percent of basin controlled by lakes swamps and reservoirs - see WRIR 00 4189 | percent | percent |
| CONVEY | Bank_Full_Channel_Conveyance | Conveyance of main stream channel at bank-full conditions | cubic feet per second | m3 per second |
| COUNTY | County_Code | County code | dimensionless | dimensionless |
| CROPSNLCD01 | Cultivated_Crops_NLCD_2001 | Percentage of area cultivated crops, NLCD 2001 category 82 | percent | percent |
| CROPSNLCD06 | Percent_Cultivated_Crops_from_NLCD2006 | Percentage of area of cultivated crops from NLCD 2006 class 82 | percent | percent |
| CRSDFT | Percent_Coarse_Stratified_Drift | Percentage of area of coarse-grained stratified drift | percent | percent |
| CRSTILL | Percent_Coarse_Till | Percentage of area of coarse till | percent | percent |
| CSL10_85 | Stream_Slope_10_and_85_Method | Change in elevation between points 10 and 85 percent of length along main channel to basin divide divided by length between points | feet per mi | m per km |
| CSL10_85fm | Stream_Slope_10_and_85_Method_ft_per_mi | Change in elevation between points 10 and 85 percent of length along main channel to basin divide divided by length between points ft per mi | feet per mi | m per km |
| CSL1085LFP | Stream_Slope_10_and_85_Longest_Flow_Path | Change in elevation between points 10 and 85 percent of length along the longest flow path determined by a GIS divided by length between the points | feet per mi | m per km |
| CSLArc10 | Stream_Slope_ArcHydro_Method_10m_DEM | Stream slope computed using method from ArcHydro Tools and 10 meter DEM | percent | percent |
| CSLBlue | Stream_Slope_Blue_Line_Method | Change in elevation of the longest blue-line stream divided by stream length | feet per mi | m per km |
| CSLBlue_ff | Main_Channel_Slope_ft_per_ft | Change in elevation of the longest blue-line stream divided by stream length | feet per foot | m per m |
| CUSL1085LFP | Stream_Slope_10_and_85_Upper_Half | Change in elevation between points 10 and 85 percent of length along the upper half of the longest flow path divided by length between the points | feet per mi | m per km |
| DA1000 | Drainage_Area_Divided_By_1000 | Drainage area divided by 1000 | square miles | km2 |
| DATUM | Datum_of_Latitude_Longitude | Datum used to determine the site coordinates | dimensionless | dimensionless |
| DAUNREG | Unregulated_Drainage_Area | Unregulated drainage area used in OK regulated equations | square miles | km2 |
| DECAVPRE | Mean_December_Precipitation | Mean December Precipitation | inches | mm |
| DECAVTMP | Mean_December_Temperature | Mean December Temperature | degrees F | degrees C |
| DECIDNLCD06 | Percent_Deciduous_from_NLCD2006 | Percentage of deciduous forest from NLCD 2006 class 41 | percent | percent |
| DESMOIN | Des_Moines_Lobe | Area underlain by Des Moines Lobe | square miles | km2 |
| DETEN | Percent_Lake_and_Detention_Basin | Percentage of area of lakes and detention basins | percent | percent |
| DEV_CH_92_01 | Percent_Diff_Developed_NLCD1992_to_2001 | Percent Difference between 1992 and 2001 area covered by developed land using NLCD | percent | percent |
| DEVHINLCD01 | High_developed_NLCD_2001 | Percentage of area developed, high intensity, NLCD 2001 category 24 | percent | percent |
| DEVHINLCD06 | Percent_Low_Developed_from_NLCD2006 | Percentage of area developed, high intensity, from NLCD 2006 class 24 | percent | percent |
| DEVLOWNLCD06 | Percent_Low_Developed_from_NLCD2006 | Percentage of developed area, low intensity, from NLCD 2006 class 22 | percent | percent |
| DEVMEDNLCD01 | Medium_developed_NLCD_2001 | Percentage of area developed, medium intensity, NLCD 2001 category 23 | percent | percent |
| DEVMEDNLCD06 | Percent_Medium_developed_NLCD_2006 | Percentage of area developed, medium intensity, NLCD 2006 class 23 | percent | percent |
| DEVNLCD01 | Percent_developed_from_NLCD2001 | Percentage of land-use categories 21-24 from NLCD 2001 | percent | percent |
| DEVNLCD06 | Percent_Developed_from_NLCD2006 | Percentage of land-use from NLCD 2006 classes 21-24 | percent | percent |
| DEVNLCD92 | Percent_Developed_from_NLCD1992 | Percentage of developed land-use categories 21-23 from NLCD 1992 | percent | percent |
| DEVOPENNLCD06 | Percent_Open_Developed_from_NLCD2006 | Percentage of developed open area from NLCD 2006 class 21 | percent | percent |
| DEVPT_LU92 | Percent_Developed_from_NLCD92 | Percent Developed from NLCD92 | percent | percent |
| DINTNLCD01 | Development_Intensity_from_NLCD2001 | Impervious percentage computed as ((.10*A21+.25*A22+.65*A23+.90*A24)/DA)*100 from NLCD 2001 | percent | percent |
| DINTNLCD06 | Development_Intensity_from_NLCD2006 | Impervious percentage computed as ((.10*A21+.25*A22+.65*A23+.90*A24)/DA)*100 from NLCD 2006 | percent | percent |
| DIRECT | Directions | Directions | dimensionless | dimensionless |
| DISTANCE | Distance_from_Ungaged_Station | Distance from Ungaged Station | miles | km |
| DISTRICT | District_Code | Code of the state where the station is located. | dimensionless | dimensionless |
| DMARMAX | Normal_Daily_Max_March_Temp | Normal Daily Maximum March Temperature | degrees F | degrees C |
| DRAINQUAL | Drainage_Quality_Index_from_STATSGO | Drainage quality index from STATSGO, see http://water.usgs.gov/GIS/metadata/usgswrd/XML/ussoils.xml#Entity_and_Attribute_Information | dimensionless | dimensionless |
| DRFTPERSTR | Stratified_Drift_per_Stream_Length | Area of stratified drift per unit of stream length | square mile per mile | km2 per km |
| DRN | Drainage_Quality | Drainage quality (1=well drained to 7=poorly drained) from dataset at http://water.usgs.gov/GIS/metadata/usgswrd/XML/ussoils.xml | dimensionless | dimensionless |
| DRNAREA | Drainage_Area | Area that drains to a point on a stream | square miles | km2 |
| DRNDENSITY | Basin_Drainage_Density | Basin drainage density defined as total stream length divided by drainage area. | miles per square mile | km per km2 |
| DRNFREQ | Drainage_Frequency | Number of first order streams per square mile of drainage area | per square mile | per km2 |
| DURREG | Flow_Duration_Region_Code | Flow-Duration Hydrologic Region code | dimensionless | dimensionless |
| DV_OF_DA | Dev_Land_percentage | Developed Land in Percentage of Drainage Area (Idaho Logistic Regression Equations SIR 2006-5035 | percent | percent |
| DWARFNLCD06 | Percent_Dwarf_Scrub_from_NLCD2006 | Percentage of dwarf scrub from NLCD 2006 class 51 | percent | percent |
| EFFECTDA | Effective_Drainage_Area | Total drainage area minus area upstream from erosion-control and flood-retention structures | square miles | km2 |
| EL1200 | Percentage_of_Basin_Above_1200_ft | Percentage of basin at or above 1200 ft elevation | percent | percent |
| EL2000 | Percent_Area_Above_2000_ft | Percent of basin area that is above 2000 feet elevation | percent | percent |
| EL5000 | Percent_above_5000_ft | Percent of area above 5000 ft | percent | percent |
| EL6000 | Percent_above_6000_ft | Percent of area above 6000 ft | percent | percent |
| EL7000 | Percent_Above_7000_ft | Percent of area above 7000 ft | feet | m |
| EL7500 | Percent_above_7500_ft | Percent of area above 7500 ft | percent | percent |
| ELEV | Mean_Basin_Elevation | Mean Basin Elevation | feet | m |
| ELEV1000 | Elevation_in_Thousands | Elevation in Thousands | thousand feet | kilometer |
| ELEV10FT | Elev_10pct_LFP_from_DEM | Elevation at 10 percent from outlet along longest flow path slope using DEM | feet | m |
| ELEV10FT3D | Elev_10pct_LFP_from_3Dline | Elevation at 10 percent from outlet along longest flow path slope using 3D line | feet | m |
| ELEV85FT | Elev_85pct_LFP_from_DEM | Elevation at 85 percent from outlet along longest flow path slope using DEM | feet | m |
| ELEV85FT3D | Elev_85pct_LFP_from_3Dline | Elevation at 85 percent from outlet along longest flow path slope using 3D line | feet | m |
| ELEVMAX | Maximum_Basin_Elevation | Maximum basin elevation | feet | m |
| ELONGRATIO | Elongation_Ratio | Elongation Ratio | dimensionless | dimensionless |
| ELV10_85 | Elevation_of_10_and_85_points | Average of channel elevations at points 10- and 85- percent above gage - Equivalent to Altitude Index | feet | m |
| EMERGWETNLCD06 | Percent_Emergent_Wetlands_from_NLCD2006 | Percentage of area of emergent herbaceous wetlands from NLCD 2006 class 95 | percent | percent |
| END_REC | End_date_of_record | Last day of record | days | days |
| EVAP | Mean_Annual_Lake_Evaporation | Mean Annual Lake Evaporation | inches | mm |
| EVAPAN | Mean_Annual_Pan_Evaporation | Mean Annual Pan Evaporation | inches | mm |
| EVERGRNLCD01 | Evergreen_Forest_NLCD_2001 | Percentage of area evergreen forest, NLCD 2001 category 42 | percent | percent |
| EVERGRNLCD06 | Percent_Evergreen_Forest_NLCD_2006 | Percentage of evergreen forest from NLCD 2006 class 42 | percent | percent |
| FDRATIO | Flow_Duration_Ratio | 20-percent flow duration divided by 90-percent flow duration | dimensionless | dimensionless |
| FEBAVPRE | Mean_February_Precipitation | Mean February Precipitation | inches | mm |
| FEBAVTMP | Mean_February_Temperature | Mean February Temperature | degrees F | degrees C |
| FINMOR | Percent_Fine_End_Moraine | Percentage of area of end moraine fine till | percent | percent |
| FIRSTYEAR | First_Year_of_Record | Year in which record was first collected or used for analysis | years | years |
| FOR_CH_92_01 | Percent_Diff_Forest_NLCD1992_to_2001 | Percent Difference between 1992 and 2001 area covered by forest using NLCD | percent | percent |
| FOREST | Percent_Forest | Percentage of area covered by forest | percent | percent |
| FOREST_MD | Percent_forest_from_MD_2010_land_use | Percent forest from Maryland 2010 land-use data | percent | percent |
| FORESTNLCD01 | Percent_Forest_from_NLCD2001 | Percentage of forest from NLCD 2001 classes 41-43 | percent | percent |
| FORESTNLCD06 | Percent_Forest_from_NLCD2006 | Percentage of forest from NLCD 2006 classes 41-43 | percent | percent |
| FORESTNLCD92 | Percent_Forest_from_NLCD1992 | Percentage of forest from NLCD 1992 classes 41-43 | percent | percent |
| FORESTp1 | Percent_Forest_add_1_ID_ROI_Parm | Percent Forest plus 1 (ID ROI Parm) | dimensionless | dimensionless |
| FORMD97 | Percent_Forest_MDOP97 | Percent area of forest from Maryland Dept of Planning 1997 land-use data | percent | percent |
| FORUPLLU92 | Percent_Forested_Upland_from_NLCD1992 | Percent Forested Upland from NLCD1992 | percent | percent |
| FOSTREAM | Number_of_First_Order_Streams | Number of first order streams determined using the Strahler stream ordering system | dimensionless | dimensionless |
| FROST | Mean_February_28_Frost_Depth | Mean frost depth on February 28 | inches | mm |
| GEOFACTVT | Geographic_Factor_for_VT | Northing of the centroid of the drainage basin in the Vermont State Plane coordinate system divided by 100000 then increased by 1 | dimensionless | dimensionless |
| GEOFACTWY | Geographic_Factor_for_WY | Geographic factor for Wyoming from plate 1 of Lohman (1988) | dimensionless | dimensionless |
| GLACIATED | Percent_of_Glaciation | Percentage of basin area that was historically covered by glaciers | percent | percent |
| GLACIER | Percent_Glaciers | Percentage of area of Glaciers | percent | percent |
| GRASSNLCD06 | Percent_Grassland_from_NLCD2006 | Percentage of grassland from NLCD 2006 class 71 | percent | percent |
| GUTTER | Gutter_Length | Length of gutters per square mile of drainage area | miles per square mile | km per km2 |
| GWHEAD | Groundwater_Head | Mean - minimum basin elevation | feet | m |
| HERBNLCD01 | Percent_Herbaceous_Upland_from_NLCD2001 | Percentage of herbaceous upland from NLCD 2001 class 71 | percent | percent |
| HERBNLCD06 | Percent_Herbaceous_from_NLCD2006 | Percentage of herbaceous from NLCD 2006 classes 71-74 | percent | percent |
| HIELONGRAT | Hawaii_Elongation_Ratio | Ratio of (1)diameter of circle with equal area as basin to (2)basin length, as defined in SIR 2004-5262 | dimensionless | dimensionless |
| HIGHEQU | High_Flow_Regression_Equation | Indicates whether the site was used to develop high-flow regression equations | Yes or No | Yes or No |
| HIGHREG | High_Flow_Region_Code | High-Flow Hydrologic Region code | dimensionless | dimensionless |
| HIMARRATE | Hawaii_Mean_Rainfall_Rate | Mean annual rainfall rate determined based on the method described in SIR 2004-5262 | cubic feet per second | m3 per second |
| HIRAINRATE | Maximum_Weighted_Rainfall_Rate | Maximum Weighted Rainfall Rate | cubic feet per second | m3 per second |
| HOMDEN2000 | Housing_Density_during_2000 | Housing density from 2000 census data | homes per acre | homes per km2 |
| HOMDENCYR | Housing_Density_of_Centroid_Year | Housing density for centroid year of streamflow data collection | homes per acre | homes per km2 |
| HOMEDENS | Housing_Density | Average homes per acre in watershed | homes per acre | homes per km2 |
| HRBCLTLU92 | Percent_Cult_Herb_Upland_from_NLCD1992 | Percent Cultivated Herbaceous Upland from NLCD1992 | percent | percent |
| HRBNATLU92 | Percent_Nat_Herb_Upland_from_NLCD1992 | Percent Natural Herbaceous Upland from NLCD1992 | percent | percent |
| HUC | Hydrologic_Unit_Number | Hydrologic Unit Number | dimensionless | dimensionless |
| HYPSO | Hypsometric_Area_Ratio | Single-valued index equal to the ratio of the area under the normalized hypsometric curve | dimensionless | dimensionless |
| I24H100Y | 24_Hour_100_Year_Precipitation | Maximum 24-hour precipitation that occurs on average once in 100 years | inches | mm |
| I24H10Y | 24_Hour_10_Year_Precipitation | Maximum 24-hour precipitation that occurs on average once in 10 years | inches | mm |
| I24H25Y | 24_Hour_25_Year_Precipitation | Maximum 24-hour precipitation that occurs on average once in 25 years | inches | mm |
| I24H2Y | 24_Hour_2_Year_Precipitation | Maximum 24-hour precipitation that occurs on average once in 2 years - Equivalent to precitation intensity index | inches | mm |
| I24H500Y | 24_Hour_500_Year_Precipitation | Maximum 24-hour precipitation that occurs on average once in 500 years | inches | mm |
| I24H50Y | 24_Hour_50_Year_Precipitation | Maximum 24-hour precipitation that occurs on average once in 50 years | inches | mm |
| I24H5Y | 24_Hour_5_Year_Precipitation | Maximum 24-hour precipitation that occurs on average once in 5 years | inches | mm |
| I24MAX | 24_Hour_Maximum_Precipitation | Maximum 24-hour precipitation for period of record | inches | mm |
| I2H2Y | 2_Hour_2_Year_Precipitation | Maximum 2-hour precipitation that occurs on average once in 2 years | inches | mm |
| I48H100Y | 48_Hour_100_Year_Precipitation | Maximum 48-hour precipitation that occurs on average once in 100 years | inches | mm |
| I48H10Y | 48_Hour_10_Year_Precipitation | Maximum 48-hour precipitation that occurs on average once in 10 years | inches | mm |
| I48H25Y | 48_Hour_25_Year_Precipitation | Maximum 48-hour precipitation that occurs on average once in 25 years | inches | mm |
| I48H2Y | 48_Hour_2_Year_Precipitation | Maximum 48-hour precipitation that occurs on average once in 2 years | inches | mm |
| I48H500Y | 48_Hour_500_Year_Precipitation | Maximum 48-hour precipitation that occurs on average once in 500 years | inches | mm |
| I48H50Y | 48_Hour_50_Year_Precipitation | Maximum 48-hour precipitation that occurs on average once in 50 years | inches | mm |
| I48H5Y | 48_Hour_5_Year_Precipitation | Maximum 48-hour precipitation that occurs on average once in 5 years | inches | mm |
| I60M100Y | 60_Min_100_Year_Precipitation | Maximum 60-min precipitation that occurs on average once in 100 years | inches | mm |
| I60M10Y | 60_Min_10_Year_Precipitation | Maximum 60-min precipitation that occurs on average once in 10 years | inches | mm |
| I60M25Y | 60_Min_25_Year_Precipitation | Maximum 60-min precipitation that occurs on average once in 25 years | inches | mm |
| I60M2Y | 60_Min_2_Year_Precipitation | Maximum 60-min precipitation that occurs on average once in 2 years | inches | mm |
| I60M500Y | 60_Min_500_Year_Precipitation | Maximum 60-min precipitation that occurs on average once in 500 years | inches | mm |
| I60M50Y | 60_Min_50_Year_Precipitation | Maximum 60-min precipitation that occurs on average once in 50 years | inches | mm |
| I60M5Y | 60_Min_5_Year_Precipitation | Maximum 60-min precipitation that occurs on average once in 5 years | inches | mm |
| I6H100Y | 6_Hour_100_Year_Precipitation | 6-hour precipitation that is expected to occur on average once in 100 years | inches | mm |
| I6H10Y | 6_Hour_10_Year_Precipitation | Maximum 6-hour precipitation that occurs on average once in 10 years | inches | mm |
| I6H25Y | 6_Hour_25_Year_Precipitation | Maximum 6-hour precipitation that occurs on average once in 25 years | inches | mm |
| I6H2Y | 6_Hour_2_Year_Precipitation | Maximum 6-hour precipitation that occurs on average once in 2 years | inches | mm |
| I6H500Y | 6_Hour_500_Year_Precipitation | Maximum 6-hour precipitation that occurs on average once in 500 years | inches | mm |
| I6H50Y | 6_Hour_50_Year_Precipitation | Maximum 6-hour precipitation that occurs on average once in 50 years | inches | mm |
| I6H5Y | 6_Hour_5_Year_Precipitation | Maximum 6-hour precipitation that occurs on average once in 5 years | inches | mm |
| ILREG1 | Region_1_Indicator__enter_1 | Indicator variable for IL region 1, enter 1 if site is in region 1 else 0 | dimensionless | dimensionless |
| ILREG3 | Region_3_Indicator__enter_1 | Indicator variable for IL region 3, enter 1 if site is in region 3 else 0 | dimensionless | dimensionless |
| ILREG5 | Region_5_Indicator__enter_1 | Indicator variable for IL region 5, enter 1 if site is in region 5 else 0 | dimensionless | dimensionless |
| ILREG6 | Region_6_Indicator__enter_1 | Indicator variable for IL region 6, enter 1 if site is in region 6 else 0 | dimensionless | dimensionless |
| ILREG7 | Region_7_Indicator__enter_1 | Indicator variable for IL region 7, enter 1 if site is in region 7 else 0 | dimensionless | dimensionless |
| IMPERV | Percent_Impervious | Percentage of impervious area | percent | percent |
| IMPMD97 | Percent_Impervious_MDOP97 | Percent area of impervioud surfaces from Maryland Dept of Planning 1997 land-use data | percent | percent |
| IMPNLCD01 | Percent_Impervious_NLCD2001 | Percentage of impervious area determined from NLCD 2001 impervious dataset | percent | percent |
| IMPNLCD06 | Percent_Impervious_NLCD2006 | Percentage of impervious area determined from NLCD 2006 impervious dataset | percent | percent |
| JANAVPRE | Mean_January_Precipitation | Mean January Precipitation | inches | mm |
| JANAVTMP | Mean_January_Temperature | Mean January Temperature | degrees F | degrees C |
| JANMAXTMP | Mean_Maximum_January_Temperature | Mean Maximum January Temperature | degrees F | degrees C |
| JANMINTMP | Mean_Min_January_Temperature | Mean Minimum January Temperature | degrees F | degrees C |
| JULAVPRE | Mean_July_Precipitation | Mean July Precipitation | inches | mm |
| JULYAVEPRE | Mean_July_Precipitation | Mean July Precipitation | dimensionless | dimensionless |
| JULYAVTMP | Mean_July_Temperature | Mean July Temperature | degrees F | degrees C |
| JULYMAXTMP | Mean_Max_July_Temperature | Mean Maximum July Temperature | degrees F | degrees C |
| JULYMIN | Mean_Minimum_July_Temperature | Mean Minumum July Temperature | degrees F | degrees C |
| JUNAVPRE | Mean_June_Precipitation | Mean June Precipitation | inches | mm |
| JUNEAVPRE | Mean_June_Precipitation | Mean June Precipitation | dimensionless | dimensionless |
| JUNEAVTMP | Mean_June_Temperature | Mean June Temperature | degrees F | degrees C |
| KY_C_FACTOR | KY_Optimal_Cutpoint_Coefficient | Coefficient to adjust to optimal cutpoint probability in PZero equations for KY in SIR 2010-5217 | dimensionless | dimensionless |
| KYVAR_INDEX | KY_Variability_Index | Variability Index as defined by KY WRIR 1991-4097 | dimensionless | dimensionless |
| LAGFACTOR | Lag_Factor | Lag Factor as defined in SIR 2006-5112 | dimensionless | dimensionless |
| LAGTIME | Lagtime | Elapsed time from center of mass of rainfall excess to center of mass of flood hydrograph | hours | hours |
| LAKEAREA | Percent_Lakes_and_Ponds | Percentage of Lakes and Ponds | percent | percent |
| LAKESp1 | Percent_Lakes_add_1_MN_ROI_Parm | Percent Lakes plus 1 (MN ROI Parm) | dimensionless | dimensionless |
| LASTYEAR | Last_Year_of_Record | Year in which record was last collected or used for analysis | years | years |
| LAT_CENT | Latitude_of_Basin_Centroid | Latitude of Basin Centroid | decimal degrees | decimal degrees |
| LAT_GAGE | Latitude | Latitude | decimal degrees | decimal degrees |
| LAT_NHD | Latitude_on_NHD | Latitude of station location on National Hydrography Dataset | degrees | degrees |
| LAT_OUT | Latitude_of_Basin_Outlet | Latitude of Basin Outlet | degrees | degrees |
| LENGTH | Main_Channel_Length | Length along the main channel from the measuring location extended to the basin divide | miles | km |
| LFPLENGTH | LFP_length | Length of longest flow path | miles | km |
| LICHENNLCD06 | Percent_Lichens_from_NLCD2006 | Percentage of lichens from NLCD 2006 class 73 | percent | percent |
| LIME | Percent_Limestone | Percentage of area of limestone geology | percent | percent |
| LNG_GAGE | Longitude | Longitude | decimal degrees | decimal degrees |
| LOESSDEP | Loess_Depth | Depth of loess deposits | feet | m |
| LOGDA | Log_of_Drainage_Area | Logarithm base 10 of drainage area | Log base 10 | Log base 10 |
| LOGDA1000 | Log_Of_Drainage_Area_Divided_By_1000 | Log of drainage area divided by 1000 | Log base 10 | Log base 10 |
| LOGPREC28 | Log_Of_Mean_Annual_Precip_Divided_By_28 | Log of mean annual precipitation from PRISM divided by 28 | inches | mm |
| LON_NHD | Longitude_on_NHD | Longitude of station location on National Hydrography Dataset | degrees | degrees |
| LONG_CENT | Longitude_of_Basin_Centroid | Longitude Basin Centroid | decimal degrees | decimal degrees |
| LONG_OUT | Longitude_of_Basin_Outlet | Longitude of Basin Outlet | degrees | degrees |
| LONGESTFP | Longest_Flow_Path | Longest distance along stream from site of interest to top of basin | miles | km |
| LOWEQU | Low_Flow_Regression_Equation | Indicates whether the site was used to develop low-flow regression equations | Yes or No | Yes or No |
| LOWREG | Low_Flow_Region_Code | Low-Flow Hydrologic Region code | dimensionless | dimensionless |
| LSTPERM | Least_Permeable_Layer_Permeability | Permeability of least permeable layer | inches per hour | mm per hr |
| LU12 | Sum_of_Land_Use_I_and_II | Index based on the sum of land use types I and II in Portland-Vancouver WA | square miles | km2 |
| MAPM | Mean_Annual_Precip_Basin_Average | Mean Annual Precip Basin Average | inches | mm |
| MARAVPRE | Mean_March_Precipitation | Mean March Precipitation | inches | mm |
| MARAVTMP | Mean_March_Temperature | Mean March Temperature | degrees F | degrees C |
| MAREGION | Massachusetts_Region | Region of Massachusetts 0 for Eastern 1 for Western | dimensionless | dimensionless |
| MARMAXTMP | Mean_Max_March_Temperature | Mean Maximum March Temperature | degrees F | degrees C |
| MAXBSLOPD | Maximum_Basin_Slope_in_deg | Maximum basin slope, in degrees, using ArcInfo Grid with NHDPlus 30-m resolution elevation data. | degrees | degrees |
| MAXTEMP | Mean_Annual_Max_Temperature | Mean annual maximum air temperature over basin surface area as defined in SIR 2008-5126 | degrees F | degrees C |
| MAYAVPRE | Mean_May_Precipitation | Mean May Precipitation | inches | mm |
| MAYAVTMP | Mean_May_Temperature | Mean May Temperature | degrees F | degrees C |
| MCD | MCD_Code | MCD Code | dimensionless | dimensionless |
| MCSP | Main_Channel_Slope_Proportion | Main channel slope proportion computed by Basinsoft as main channel length divided by the square root of the main channel slope | dimensionless | dimensionless |
| MCSRBSFT | Main_Channel_Sinuosity_Ratio | Main-channel sinuosity ratio computed by Basinsoft as main channel length divided by basin length | dimensionless | dimensionless |
| MDAREA | Drainage_Area_in_Maryland | Drainage area of the basin within the State of Maryland | square miles | km2 |
| MEDPREC | Median_Annual_Precipitation | Median Annual Precipitation | inches | mm |
| MEDTILL | Percent_Medium_Till | Percentage of area of medium-textured glacial till | percent | percent |
| MINBELEV | Minimum_Basin_Elevation | Minimum basin elevation | feet | m |
| MINBSLOPD | Minimum_Basin_Slope_in_deg | Minimum basin slope, in degrees, using ArcInfo Grid with NHDPlus 30-m resolution elevation data. | degrees | degrees |
| MINTEMP | Mean_Annual_Min_Temperature | Mean annual minimum air temperature over basin surface area as defined in SIR 2008-5126 | degrees F | degrees C |
| MIXFOR | Percent_Mixed_Forest | Percentage of land area covered by mixed deciduous and coniferous forest | percent | percent |
| MIXFORNLCD06 | Percent_Mixed_Forest_from_NLCD2006 | Percentage of mixed deciduous and evergreen forest from NLCD 2006 class 43 | percent | percent |
| MONREG | Monthly_and_Annual_Region_Code | Monthly and Annual Hydrologic Region code | dimensionless | dimensionless |
| MORTILL | End_Moraines_of_Fine_Textured_Till | Percentage of End Moraines of Fine-Textured Till | percent | percent |
| MOSSNLCD06 | Percent_Moss_from_NLCD2006 | Percentage of moss from NLCD 2006 class 74 | percent | percent |
| MSTPERM | Most_Permeable_Layer_Permeability | Permeability of the most permeable layer | inches per hour | mm per hr |
| MUCK | Percent_Peat_and_Muck | Percentage of area of peat and muck | percent | percent |
| MXSNO | Median_Seasonal_Maximum_Snow_Depth | 50th percentile of seasonal maximum snow depth from Northeast Regional Climate Center atlas by Cember and Wilks, 1993 | inches | mm |
| NDAY_REC | Number_of_days_of_record | Number of days of record | days | days |
| NDAYSGT0 | Number_of_days_GT_0 | Number of days with flow greater than zero | days | days |
| NFSL30 | North_Facing_Slopes_Grt_Than_30_Percent | North-Facing Slopes Greater Than 30 Percent | percent | percent |
| NFSL30_10M | N_Facing_Slopes_gt_30pct_from_10m_NED | Percent area with north-facing slopes greater than 30 percent from 10-meter NED. | percent | percent |
| NFSL30_30M | N_Facing_Slopes_gt_30pct_from_30m_DEM | Percent area with north-facing slopes greater than 30 percent from 30-meter DEM. | percent | percent |
| NOVAVPRE | Mean_November_Precipitation | Mean November Precipitation | inches | mm |
| NOVAVTMP | Mean_November_Temperature | Mean November Temperature | degrees F | degrees C |
| OCTAVPRE | Mean_October_Precipitation | Mean October Precipitation | inches | mm |
| OCTAVTMP | Mean_October_Temperature | Mean October Temperature | degrees F | degrees C |
| OH_INF_IND | Ohio_Infiltration_Index | Index of relative infiltration from Koltun(1986) | dimensionless | dimensionless |
| OHCLFAC100 | Ohio_Climate_Factor_100_Year | Ohio Climate Factor 100 Year | dimensionless | dimensionless |
| OHCLFAC2 | Ohio_Climate_Factor_2_Year | Ohio Climate Factor 2 Year | dimensionless | dimensionless |
| OHCLFAC25 | Ohio_Climate_Factor_25_Year | Ohio Climate Factor 25 Year | dimensionless | dimensionless |
| OHPHYSSECT | Ohio_Physiographic_Sections | Ohio Physiographic Sections | dimensionless | dimensionless |
| OHREG_CODE | Ohio_Flood_Region_Letter_Code | Ohio Flood Region Letter Code | dimensionless | dimensionless |
| OHREGA | Ohio_Region_A_Indicator_1_if_in_A_else_0 | Ohio Region A Indicator | dimensionless | dimensionless |
| OHREGC | Ohio_Region_C_Indicator_1_if_in_C_else_0 | Ohio Region C Indicator | dimensionless | dimensionless |
| OmegaEM | OmegaEM_residual_from_2009_5087 | Generalized regression residual as defined in TX SIR 2009-5087 | dimensionless | dimensionless |
| OPENLOWNLCD01 | Open_and_Low_NLCD_2001 | Percentage of area developed, open space and low intensity combined, NLCD2001 cat. 21 and 22 | percent | percent |
| OPENLOWNLCD06 | Percent_Open_and_Low_Developed_NLCD_2006 | Percentage of area developed, open space and low intensity combined, NLCD2006 classes 21 and 22 | percent | percent |
| OR_HIPERMA | OR_Percent_HighPerm_Aquifer | Percent basin surface area containing high permeability aquifer units as defined in SIR 2008-5126 | percent | percent |
| OR_HIPERMG | OR_Percent_HighPerm_Geologic | Percent basin surface area containing high permeability geologic units as defined in SIR 2008-5126 | percent | percent |
| ORDOMISS | Percent_SurficialGeology_Ordo_and_Miss | Percent Surficial Geology as Ordovician and Mississippian Rocks | percent | percent |
| OTHEQU | Other_Regression_Equation | Indicates whether the site was used to develop regression equations for other than high or low flows | Yes or No | Yes or No |
| OUTLETELEV | Elevation_of_Gage | Elevation of the stream outlet in thousands of feet above NAVD88. | feet | m |
| OUTLETX | Basin_Outlet_X | Basin outlet horizontal (x) location in state plane coordinates | State plane coordinates | State plane coordinates |
| OUTLETY | Basin_Outlet_Y | Basin outlet vertical (y) location in state plane coordinates | State plane coordinates | State plane coordinates |
| OUTWASH | Percent_Outwash | Percentage of area of outwash | percent | percent |
| PASTURENLCD06 | Percent_Pasture_from_NLCD2006 | Percentage of area of pasture area from NLCD 2006 class 81 | percent | percent |
| PCLAY | Percent_Lacustrine_Clay_and_Silt | Percentage of lacustrine clay and silt | percent | percent |
| PCTREG1 | Percent_Area_in_Region_1 | Percentage of drainage area located in Region 1 | percent | percent |
| PCTREG2 | Percent_Area_in_Region_2 | Percentage of drainage area located in Region 2 | percent | percent |
| PCTREG3 | Percent_Area_in_Region_3 | Percentage of drainage area located in Region 3 | percent | percent |
| PCTREG4 | Percent_Area_in_Region_4 | Percentage of drainage area located in Region 4 | percent | percent |
| PCTREG5 | Percent_Area_in_Region_5 | Percentage of drainage area located in Region 5 | percent | percent |
| PCTSNDGRV | Percent_Underlain_By_Sand_And_Gravel | Percentage of land surface underlain by sand and gravel deposits | percent | percent |
| PERM12IN | Soil_permeability_top_12_in | Area-weighted average soil permeability for top 12 inches of soil | inches per hour | mm per hr |
| PERM24IN | Soil_permeability_top_24_in | Area-weighted average soil permeability for top 24 inches of soil | inches per hour | mm per hr |
| PERMGTE2IPH | Percent_permeability_gte_2_in_per_hr | Percent of area underlain by soils with permeability greater than or equal to 2 inches per hour | percent | percent |
| PERREC | Period_of_record | Period of record | years | years |
| PLANTNLCD06 | Percent_Planted_from_NLCD2006 | Percentage of planted area from NLCD 2006 classes 81 and 82 | percent | percent |
| PLCHSWAMP | Percent_Length_of_Main_Channel_Swamps | Percentage of the main channel length that flows through swamps | percent | percent |
| POPDENS | Basin_Population_Density | Basin Population Density | persons per square mile | persons per km2 |
| PRC1 | Mean_January_Precipitation | Mean January Precipitation | dimensionless | dimensionless |
| PRC4 | Mean_April_Precipitation | Mean April Precipitation | dimensionless | dimensionless |
| PRC8 | Mean_August_Precipitation | Mean August Precipitation | dimensionless | dimensionless |
| PRCWINTER | Mean_Annual_Winter_Precipitation | Mean annual precipitation for December through February | inches | mm |
| PREBC_1112 | Nov_to_Dec_Basin_Centroid_Precip | Mean annual precipitation of basin centroid for November 1 to December 31 period | inches | mm |
| PREBC0103 | Jan_to_Mar_Basin_Centroid_Precip | Mean annual precipitation of basin centroid for January 1 to March 15 winter period | inches | mm |
| PREC10to4 | Mean_Oct_to_Apr_Precipitation | Mean precipitation for winter period defined as October to April | inches | mm |
| PRECIP | Mean_Annual_Precipitation | Mean Annual Precipitation | inches | mm |
| PRECIP28 | Mean_Annual_Precipitation_Divided_By_28 | Mean annual precipitation from PRISM divided by 28 | inches | mm |
| PRECIPCENT | Mean_Annual_Precip_at_Basin_Centroid | Mean Annual Precip at Basin Centroid | inches | mm |
| PRECIPOUT | Mean_Annual_Precip_at_Gage | Mean annual precip at the stream outlet (based on annual PRISM precip data in inches from 1971-2000) | inches | mm |
| PRECless35 | Mean_Annual_Precip_less_35_LA_ROI_Parm | Mean Annual Precip - 35 (LA ROI Parm) | inches | mm |
| PREG_03_05 | Mar_to_May_Gage_Precipitation | Mean precipitation at gaging station location for March 16 to May 31 spring period | inches | mm |
| PREG_06_10 | Jun_to_Oct_Gage_Precipitation | Mean precipitation at gaging station location for June to October summer period | inches | mm |
| PREG_11_05 | Nov_to_May_Gage_Precipitation | Mean monthly precipitation for Novermber through May at the stream outlet | inches | mm |
| PREMARAPR | Basin_Ave_Rainfall_Mar_Apr | Precipitation March-April basin average, mean monthly as defined in SIR 2008-5065 | inches | mm |
| PRENOVAPR | Basin_Ave_Rainfall_Nov_Apr | Precipitation November-April basin average, mean monthly as defined in SIR 2008-5065 | inches | mm |
| PRENOVDEC | Basin_Ave_Rainfall_Nov_Dec | Precipitation November-December basin average, mean monthly as defined in SIR 2008-5065 | inches | mm |
| PSFSLp1 | Pct_South_Facing_Slopes_add_1_ID_ROI | Pct. South Facing Slopes plus 1 (ID ROI Parm) | dimensionless | dimensionless |
| PWIN_ME | Dec_to_Feb_Mean_Precipitation | Mean annual precipitation for winter defined for Maine as December to February | inches | mm |
| RCN | Runoff_Curve_Number | Runoff-curve number as defined by NRCS (http://policy.nrcs.usda.gov/OpenNonWebContent.aspx?content=17758.wba) | dimensionless | dimensionless |
| RCNMD97 | Runoff_Curve_Number_MOP97 | Runoff curve number determined from STATSGO soils and MD Dept of Planning 1997 land use | dimensionless | dimensionless |
| RECESS | Recession_Index | Number of days required for streamflow to recede one order of magnitude when hydrograph is plotted on logarithmic scale | days per log cycle | days per log cycle |
| REGULATE | Regulated | Indicates whether flow at the site is affected by regulations or diversions | Yes or No | Yes or No |
| RELIEF | Relief | Maximum - minimum elevation | feet | m |
| RELRELF | Relative_Relief | Basin relief divided by basin perimeter | feet per mi | m per km |
| REMARKS | Remarks | Remarks | dimensionless | dimensionless |
| RESMD97 | Percent_Residential_MDOP97 | Percent area of residential land use from Maryland Dept of Planning 1997 land-use data | percent | percent |
| ROCKDEP | Depth_to_Rock | Depth to rock | feet | m |
| ROIREGN | ROI_Region_ID | ID for the radius of Influence region | dimensionless | dimensionless |
| ROTUNDBSFT | Rotundity_of_Basin_from_Basinsoft | Rotundity of basin from Basinsoft computed as 0.785 times shape factor | dimensionless | dimensionless |
| RUGGED | Ruggedness_Number | Ruggedness number computed as stream density times basin relief | feet per mi | m per km |
| RUNCOEF | Runoff_Coefficient | Soil runoff coefficient defined in Davis (1975) | dimensionless | dimensionless |
| SANDGRAV | Fraction_Underlain_By_Sand_And_Gravel | Fraction of land surface underlain by sand and gravel deposits | dimensionless | dimensionless |
| SCRUBNLCD06 | Percent_Scrub_from_NLCD2006 | Percentage of scrub from NLCD 2006 classes 51 and 52 | percent | percent |
| SEDGENLCD06 | Percent_Sedge_from_NLCD2006 | Percentage of sedge from NLCD 2006 class 72 | percent | percent |
| SEPAVPRE | Mean_September_Precipitation | Mean September Precipitation | inches | mm |
| SEPAVTMP | Mean_September_Temperature | Mean September Temperature | degrees F | degrees C |
| SHAPE | Shape_Factor | Shape Factor for Area | dimensionless | dimensionless |
| SHAPEBSFT | Shape_Factor_from_Basinsoft | Shape factor from Basinsoft computed as basin length divided by basin width | dimensionless | dimensionless |
| SHRUBNLCD06 | Percent_Shrub_from_NLCD2006 | Percentage of shrub scrub from NLCD 2006 class 52 | percent | percent |
| SINUOS | Main_Channel_Sinuosity | Main Channel Sinuosity | miles per mile | km per km |
| SLENRAT | Slenderness_Ratio | Main channel length - squared - divided by the contributing drainage area | dimensionless | dimensionless |
| SLOP30 | Slopes_Greater_Than_30_Percent | Slopes Greater Than 30 Percent | percent | percent |
| SLOP30_10M | Slopes_gt_30pct_from_10m_NED | Percent area with slopes greater than 30 percent from 30-meter NED. | percent | percent |
| SLOP30_30M | Slopes_gt_30pct_from_30m_DEM | Percent area with slopes greater than 30 percent from 30-meter DEM. | percent | percent |
| SLOP50 | Slopes_Greater_Than_50_Percent | Slopes Greater Than 50 Percent as percent of drainage area | percent | percent |
| SLOPERAT | Slope_Ratio | Slope ratio computed as main channel slope divided by basin slope | dimensionless | dimensionless |
| SLOPERATIO | Slope_Ratio_NY | Ratio of main channel slope to basin slope as defined in SIR 2006-5112 | dimensionless | dimensionless |
| SLPFM3D | LFP_slope_3Dline | Longest flow path slope using 3D line | feet per mi | m per km |
| SN10 | 10_Yr_Max_Mar_15_Snow_Water_Equiv | Maximum March 15 Water Equivalent of Snow Cover at 10-Year Recurrence Interval | inches | mm |
| SN100 | 100_Yr_Max_Mar_15_Snow_Water_Equiv | Maximum March 15 Water Equivalent of Snow Cover at 100-Year Recurrence Interval | inches | mm |
| SN2 | 2_Yr_Max_Mar_15_Snow_Water_Equiv | Maximum March 15 Water Equivalent of Snow Cover at 2-Year Recurrence Interval | inches | mm |
| SN25 | 25_Yr_Max_Mar_15_Snow_Water_Equiv | Maximum March 15 Water Equivalent of Snow Cover at 25-Year Recurrence Interval | inches | mm |
| SN50 | 50_Yr_Max_Mar_15_Snow_Water_Equiv | Maximum March 15 Water Equivalent of Snow Cover at 50-Year Recurrence Interval | inches | mm |
| SNOAPR | April_Mean_Snow_Water_Equiv | Mean Water Equivalent of Snow Cover in April | inches | mm |
| SNOFALL | Mean_Annual_Snowfall | Mean Annual Snowfall | inches | mm |
| SNOMAR | March_Snow_Water_Equivalent | Mean Water Equivalent of Snow Cover in March | inches | mm |
| SNOWATER | Mean_Snow_Water_Equivalent | Water Equivalent of Mean Annual Snowfall | inches | mm |
| SNOWICENLCD06 | Percent_Snow_&_Ice_NLCD2006 | Percent snow and ice from NLCD 2006 class 12 | percent | percent |
| SOIL_INF | Soil_Infiltration | Soil infiltration index from NRCS | inches | mm |
| SOILA | Percent_Hydrologic_Soil_Type_A | Percentage of area of Hydrologic Soil Type A | percent | percent |
| SOILASSTATSGO | STATSGO_Percent_Hydrologic_Soil_Type_A | Percentage of area of Hydrologic Soil Type A from STATSGO | percent | percent |
| SOILASSURGO | SSURGO_Percent_Hydrologic_Soil_Type_A | Percentage of area of Hydrologic Soil Type A from SSURGO | percent | percent |
| SOILBSSTATSGO | STATSGO_Percent_Hydrologic_Soil_Type_B | Percentage of area of Hydrologic Soil Type B from STATSGO | percent | percent |
| SOILBSSURGO | SSURGO_Percent_Hydrologic_Soil_Type_B | Percentage of area of Hydrologic Soil Type B from SSURGO | percent | percent |
| SOILCorD | Percent_SSURGO_Soil_Type_C_or_D | Percentage of area of Hydrologic Soil Type C or D from SSURGO | percent | percent |
| SOILCSSTATSGO | STATSGO_Percent_Hydrologic_Soil_Type_C | Percentage of area of Hydrologic Soil Type C from STATSGO | percent | percent |
| SOILCSSURGO | SSURGO_Percent_Hydrologic_Soil_Type_C | Percentage of area of Hydrologic Soil Type C from SSURGO | percent | percent |
| SOILD | Percent_Hydrologic_Soil_Type_D | Percentage of area of Hydrologic Soil Type D | percent | percent |
| SOILINDEX | Mean_Basin_Hydrologic_Soils_Index | Mean STATSGO Hydrologic Soils Index (from PL. 2 WRIR 03-4107 for WY) | dimensionless | dimensionless |
| SOILPERM | Average_Soil_Permeability | Average Soil Permeability | inches per hour | mm per hr |
| STAID | Station_ID | Station Identification Number | dimensionless | dimensionless |
| STANAME | Station_Name | Station Name | dimensionless | dimensionless |
| STATE | State_Code | State code | dimensionless | dimensionless |
| STATYPE | Station_type | Station type code | dimensionless | dimensionless |
| STORAGE | Percent_Storage | Percentage of area of storage (lakes ponds reservoirs wetlands) | percent | percent |
| STORAGEp1 | Percent_Storage_add_1_MN_ROI_Parm | Percent Storage plus 1 (MN ROI Parm) | dimensionless | dimensionless |
| STORDELU | Percent_Storage_from_DE_Dataset | Percentage of wetlands and water bodies determined from 2003 Delaware land-use dataset | percent | percent |
| STORMD97 | Percent_Storage_MDOP97 | Percent area of storage (wetlands and water bodies) from Maryland Dept of Planning 1997 land-use data | percent | percent |
| STORNHD | Percent_Storage_from_NHD | Percent storage (wetlands and waterbodies) determined from 1:24K NHD | percent | percent |
| STORNLCD | Percent_Storage_from_NLCD | Percentage of water bodies and wetlands determined from the NLCD | percent | percent |
| STORNLCD06 | Percent_Storage_from_NLCD2006 | Percentage of water bodies and wetlands determined from the NLCD 2006 | percent | percent |
| STRDEN | Stream_Density | Stream Density | miles per square mile | km per km2 |
| STREAM_VAR | Streamflow_Variability_Index | Streamflow variability index as defined in WRIR 02-4068 | dimensionless | dimensionless |
| STRMTOT | Total_Stream_Length | Total length of mapped streams in basin | miles | km |
| SYNTHET | Code_to_indicate_synthesized_data | Blank if flow data were not synthesized - S if all flows were synthesized - SL if low flows were synthesized - SP if peak flows were synthesized | dimensionless | dimensionless |
| TEMP | Mean_Annual_Temperature | Mean Annual Temperature | degrees F | degrees C |
| TEMP_01_03 | Jan_to_Mar_Mean_Basinwide_Temp | Basinwide average temperature for January to March period | degrees F | degrees C |
| TEMP_06_10 | Jun_to_Oct_Mean_Basinwide_Temp | Basinwide average temperature for June to October summer period | degrees F | degrees C |
| TILROCK | Percent_Thin_Till_over_Bedrock | Percentage of area of thin glacial till over bedrock | percent | percent |
| TIMETOPK | TimeToPeak | TimeToPeak | hours | hours |
| TNCLFACT2 | Tennessee_Climate_Factor_2_Year | 2-Year Climate Factor for Tennessee | dimensionless | dimensionless |
| TNPHYSFAC | Tennessee_Physiographic_Factor | Tenessee physiographic factor, computed as described in WRIR 03-4176, p. 14 | dimensionless | dimensionless |
| TNSOILFAC | Tennessee_Soil_Factor | Tennessee soil factor, percentage of area underlain by a soil permeability greater than or equal to 2 inches per hour | dimensionless | dimensionless |
| TXURBINDEX | Texas_Urbanization_Index | Urbanization index defined in WRIR 82-18 | dimensionless | dimensionless |
| UAF_OK | Urban_Adjustment_Factor | Urban adjustment factor as described in OK WRIR 1997-4202 | dimensionless | dimensionless |
| URBAN | Percent_Urban | Percentage of basin with urban development | percent | percent |
| URBAN15 | Percent_Urban_Greater_Than_15_Percent | Basin with urban development greater than 15 percent | Yes or No | Yes or No |
| VALLEN | Valley_Length | Valley length measured along general path of floodplane from the outlet to the basin divide | miles | km |
| VOLCANIC | Percent_Volcanic | Percent of drainage area as surficial volcanic rocks as defined in SIR 2006-5035 | percent | percent |
| WACTCH | Width_Of_Active_Channel | Width of active channel | feet | m |
| WAT_LU92 | Percent_Water_from_NLCD1992 | Percent Water from NLCD1992 | percent | percent |
| WATCAP | Available_Water_Capacity | Available water capacity of the top 60 inches of soil - determined from STATSGO data | in per in | mm per mm |
| WATERNLCD06 | Percent_Water_from_NLCD2006 | Percent water from NLCD 2006 class 11 | percent | percent |
| WATWET | Percent_Open_Water_&_Herb_Wetland | Percent open water and herbaceous wetland from NLCD | percent | percent |
| WATWETNLCD06 | Percent_Water_&_Herb_Wetland_NLCD2006 | Percent open water and herbaceous wetland from NLCD 2006 classes 11 and 95 | percent | percent |
| WBANKFULL | Width_Of_Bankfull_Channel | Width of channel at bankfull | feet | m |
| WE_MAR2 | March_water_equivalent_2_year_RI | Water equivalent of snow cover as of the first week in March - 2-year recurrence interval | inches | mm |
| WETLAND | Percent_Wetlands | Percentage of Wetlands | percent | percent |
| WETLNDLU06 | Percent_Wetlands_from_NLCD2006 | Percentage of wetlands from NLCD 2006 classes 90 and 95 | percent | percent |
| WETLNDLU92 | Percent_Wetland_from_NLCD1992 | Percent Wetland from NLCD1992 | percent | percent |
| WOODWETNLCD06 | Percent_Woody_Wetlands_from_NLCD2006 | Percentage of area of wooded wetlands from NLCD 2006 class 90 | percent | percent |
